Turbine construction



Ap 1931- R. IBIRMANN 1,802,329

TURBINE CONSTRUCTION Filed Jan. 24, 1930 2 Sheets-Sheet 2 merits of a ship.

struction the critical the. last astern; stage;

terference,

fluidlt i ih s nd p ttie rly t0 ma he r- Patented Apr. 28, 1931 BINE COMPANY, OF TRENTQN, :{EW JERSEY, A CORPORATION OF NEW-J'EBSEY resents onsrnncrlon Application filed January 24 183d. Serial No. 423,001.

e imp v tl g ing nst ue ien not on y ae emp sh s h sr s lt e ti ely t els positively prevents the exhaust from the ahead stages froni i terferqing with the idle t ti n. ef th as ernblsde a l s mila way makes it impossible for the astern exh u e hit he ehee l ades- These and more detailed objects willhe appar n teemv he ol wing d se tipt en ee o jitne h with h a compa ying r ings in which: i

e- 1 s s s' e iehel V w, show t urb Wh h th nve t on. s h'fee p rsteel;

ig- 2 s e is heht t e evat n of h guiding unit; and 7' Fig. 3 is a plan view of the guiding unit.

T t b n a i s nd es by 2; h r bein m n ed he e n i su ta eat ng t sha t e o the seems eerryih'gt e e ee wheels 6' and stern wheels 10 reeeivi ingas usual, steam respectively from chests 8 and 12 into whi h team is selectively The present invention relates to elastic ih epe of perati in pp s te hre tions to produce both ahead and astern nove- Owing tov the fact that amarineturbine must p ra thr ug all a ge pe n t maxim m, t m st b eq ppe th whet is khew a a t haft f h evy, h e'e a speed of wh'ch is suiiiciently above the maximum running speed.

In view of the tact that the length of such sh f must h an shs h te m h mttmt usua e m, of ch tu n eelh e ah ad a l e v hee s es t e eine sh i i hs eam a t e'resp'e ive e ds'et the s a t a seh rg ng nt a emm h hau seein on e een rel pert eh f he a t the W e of the last ahead stage facing the wheel of he pa e bet e e e t tag s m s e e he t as es i whereby the exhaust spaceis very limited. H

However, if this space is quite short and of admitted depending upon the direction of e t ict si he se s g from the ahead e st en f t e ha t, and therefere etm t e w ll fle hi s h le es stegeeX- e t of t ship, Whi h s des rederti ig a braking eflect on the blades of the Between the last stages of the two sets of astern rotor and involving a disturbance of he ls 15 the exhaust receiving space taking l t e et e nhls ham er l mmf h cating withthedi'scharge 15 leadingto a condenser. i l

fio w with consequent loss of power and elliciency. similar braking action results from the action the steam v I ofthe astern dischargeon the blades of "the last ahead stage.

To prevent such interference, partition walls have sometimes been introduced to separate the ahead andastern dischargepassages f at least in the vicinity of the blading where the harmful interference of the ahead flow with the idle. astern blading or of the astern flow with theahead bla di ng can take place. Such partitionwaI-ls it properly shaped and curved accoinplish their purpose of guiding the flow of exhaust steam so as to prevent inhut they use'iup more axial length thaniccan be eff ciently sacrificed modern marine turbines.

Itisth broad object of the present invention to provide p a novel guide structure which m with practically no loss of'enleads the stea from either the ahead or astern hlading 5 into the exhaust casing orIvolute from whence iher'Pess' e heeesfl hsel h' he st t i nothing were interposed between the last stages, it is obvious'tha't the" discharge from either would reach the blades of'the' other creating braking aetion. In the in proved te str t eh her s, r e' e uidi means for preventing such interference said unit comprising pair ofouterarn ular rings lti fittiiig into the. asing and oined to an in ner ringvby spacedweb s between which are Carried annular fly arranged guiding elee ter Peitie s es h ests i the es, she

stage to the inner portions of the blades of the last astern stage, the axially extending legs of the elements extending towards the last ahead stage. By suitably curving the guiding elements, the exhaust from the last ahead stage is turned from its approximately axial direction to an approximate radial direction, the latter direction being substantially assumed before the exhaust passes from the guiding influence of the elements whereby there results no tendency for the exhaust to flow into the astern blading. The guiding elements have sharp inlet and discharge edges, and the steam passages between the adjacent elements may be of constant area throughout or of increasing ar a, if the space permits, to give a diffusing effect. By the provision of such guiding elen'ients and a upturned shoulder 24 on ring 18, it will be seen that the discharge from the ahead sta 'es is smoothly guided to the discharge passage without substantial loss in a manner indicated by the full arrows.

As was just stated, the guiding elements are of sufficient radial extent to turn the ahead exhaust to a substantially radial direction. They are, however, of as little radial extent as possible so as to offer a maximum passage for the exhaust from the astern stages to the discharge, the flow taking place as indicated by the dotted arrows. 5y reason of the overlapping arrangement of the guiding elements as viewed from the astern stages, the flow of astern exhaust to the ahead blading is prevented.

By the above construction it will be seen that the space between the ahead and astern wheels is so fitted out with guiding elements so that interference is prevented without any increase in size, the exhaust from either of the stages having a full unrestricted space for its passage. This feature is due to the fact that the same space, indicated by the zones where the two sets of arrows overlap, functions as part of the discharge passage for each of the separate exhausts. Since the two exhausts do not take place simultaneously, this double function of the space is possible.

It will be understood that the above description is purely illustrative of a preferred construction in connection with one form of turbine since the details of arrangement of the guiding elements, their number, etc. must necessarily depend upon the relationship of the wheels of the two portions of the turbine.

What I claim and desire to protect by Letters Patent is:

1. A turbine including a casing. a shaft, at least two spaced wheels mounted on the shaft and each including a set of buckets. means for guiding fluid to the first set of buckets for rotating the shaft in one direction, means for guiding fluid to the second set of buckets for rotati the shaft in the opposite direction, the exhaust from both sets of buckets passing into the space between the wheels, a discharge passage located radially outwardly of said space, and means for guiding the exhaust from the respective sets of buckets to the discharge passage, said means including guide vanes arranged approximately between the outer ends of the buckets of the first set and the inner ends of the buckets of the second set, and forming passages the intake ends of which are aligned with the exhaust from the first set of buckets and the discharge ends of which are directed outwardly towards the discharge passage, the guide vanes overlapping as viewed from the second set of buckets so to prevent direct passage of the exhaust from said second set to the first set. and terminating at their outer most portions to provide a passage of substantial free area from the second set of buckets to the discharge passage.

2. A turbine including a casing, a shaft, at least two spaced wheels mounted on the shaft and each including a set of buckets, means for guiding fluid to the first set of buckets for rotating the shaft in one direction, means for guiding fluid to the second set of buckets for rotating the shaft in the opposite direction, the exhaust from both sets of buckets passing into the space between the wheels, a discharge passage located radially outwardly of said space, and means for guiding the exhaust from the respective sets of buckets to the discharge passage, said means including annular guide vanes arranged approximately between the outer ends of the buckets of the first set and the inner ends of the buckets of the second set, and forming annular passages the intake ends of which are aligned with the exhaust from the first set of buckets and the discharge ends of which are directed outwardly towards the discharge passage, the guide vanes overlapping as viewed from the second set of buckets so as to prevent direct passage of the exhaust from said second set to the first set, and terminating at their outermost portions to provide a passage of substantial free area from the second set of buckets to the discharge passage.

3. A turbine including a casing, a shaft, at least two spaced wheels mounted on the shaft and each including a set of buckets. means for guiding fluid to the first set of buckets for rotating the shaft in one direction, means for guiding fluid to the second set of buckets for rotating the shaft in. the opposite direc tion, the exhaust from both sets of buckets passing into the space between the wheels. a discharge passage located radially outwardly of said space, and means for guiding the exhaust from the respective sets of buckets to the discharge passage, said means including guide vanes of L-shape in axial cross section arranged approximately between the outer ends of the buckets of the first set and the inner ends of the buckets of the second set, and forming passages the intake ends of which are aligned with the exhaust from the first set of buckets and the discharge ends of which are directed outwardly towards the discharge passage, the guide vanes overlapping as viewed from the second set of buckets 1 so as to prevent direct passage of the exhaust from said second set to the first set, and terminating at their outermost portions to provide a passage of substantial free area from the second set of buckets to the discharge passage.

4. A turbine including a casing, a shaft, at least two spaced wheels mounted on the shaft and each including a set of buckets, means for guiding'fluid to the first set of buckets for rotating the shaft in one direction, means for guiding fluid to the second set of buckets for rotating the shaft in the opposite direction, the exhaust from both sets of buckets passing into the space between the wheels, a discharge passage located radially outwardly of said space, and means for guiding the exhaust from the respective sets of buckets to the discharge passage, said means including annular guide vanes of L-shape in axial cross section arranged approximately between the outer ends of the buckets of the first set and the inner ends of the buckets of the second set, and forming annular passages the intake ends of which are aligned with the exhaust from the first set of buckets and the discharge ends of which are directed outwardly towards the discharge passage, the guide vanes overlapping as viewed from the second set of buckets so as to prevent direct passage of the exhaust from said second set to the first set, and terminating at their outermost portions to provide a passage of substantial free area from the second set of buckets to the discharge passage.

In testimony of which invention, I have hereunto set my hand, at Trenton, N. J on this 20th day of January, 1930.

V RUDOLPH BIRMANN. 

